| 摘要 |
<p>A method for making silica includes delivering a silica precursor comprising a pseudohalogen to a conversion site and passing the silica precursor through a flame to produce silica soot. The pseudohalogen is selected from a group consisting of cyano, isocyano, cyanato, isocyanato, thiocyanato, isothiocyanato, selenocyanato, and isoselenocyanato. By suitable choice of pseudohalogen (also claimed) germanium oxide can be made. The silica and/or germania may be a soot powder or deposited on a substrate, such as a rod or tube to form an optical fiber preform or on a planar substrate to form a stepper lens preform used for microlithography processes. The pseudohalogen precursors are hydrogen-free and chlorine-free.</p> |
